Every Saturday and Sunday morning dozens -- sometimes hundreds -- of self-described fitness freaks hit the stairs at Red Rocks Amphitheatre for It Burns Joe Fitness led by batshit-and-proud Joe Hendricks. "The only way we keep our numbers down from a completely uncontrollable size group is by continuously making our extreme workout harder and harder and that's why I am constantly trying to find a different muscle or killer move that spanks us all (including me)," writes Hendricks on his website. Photographer Stephen Cummings hit up Red Rocks on Saturday, July 23, 2011 and brings back these photos.